Strange ode45 behavior

Hi all,
I just tried this Matlab code:
func = @(t, y) humps(t*y);
[t y] = ode45(func, [0, 7.5], 1);
plot(t, y);
Changing the upper limit of the time range to 7 or slightly decreasing the tolerance drastically changes the solution (at least on my system, R2010b). I wonder why.
I would think that this ode is neither stiff nor unstable in any other sense. The solvers ode113 and ode23 do not show this strange behavior. Even the simplest Euler method with step size 0.01 gets a better solution. Can anyone explain, why ode45 produces such a strange solution in this case?
Thanks
Klaus

"Klaus" wrote in message <j4iisn$9vq$1@newscl01ah.mathworks.com>...
>I wonder why.
> I would think that this ode is neither stiff nor unstable in any other sense.
Mathematically not, but I just looks at the HUMPS function and it has two big peaks, and the rhs is almost "not lipschitzian" and probably ode45 has the hard time to cope with the peaks.
Intentionally HUMPS is created in order to show the robustness of QUAD but fails ODE45.
Bruno

Strange behaviorDoes anyone have clue as to what this means?
OS is 5.0.6 with patches and Merge 5.3.7c
WARNING: Merge: _M_vpg_vpte_invalidate - couldn't find vptep F1B6E400
Fri Oct 29 15:11:13 2004
WARNING: bufcall - Could not allocate STREAMS event
All tcp activity halted and this kept repeating on the console. One merge
and then the screen would roll over with the bufcall message. I could get
the login from the console, but it wouldn't let me in. I had to power cycle
to recover.
TIA
Ron
"Ronald J Marchand" <ron@rojomar.com> wrote in message
news:97083$41863e60$42a6716f$29779@msgid.meganewsservers.com...
> Does anyone have clue as to what this means?
> OS is 5.0.6 with patches and Merge 5.3.7c
>
> WARNING: Merge: _M_vpg_vpte_invalidate - couldn't find vptep F1B6E400
> Fri Oct 29 15:11:13 2004
> WARNING: bufcall - Could not allocate STREAMS event
>
> All tcp activity halted and this kept repeating on the console. One merge
> and then the screen would roll over with the bufcall message. I could get
> the login from the console, but it wouldn't let me in. I had to power
cycle
> to recover.
>
> TIA
> Ron
>
>
Hi Ron,
It looks like you're running out of streams.
If you're running samba, you could have the same problem as I had. I don't
know whether this has been submitted in later versions of samba (or later
versions of SCO)
Hope this link to my previous posts helps.
http://groups.google....

Strange behavior in TrashHi Group,
I'm on KDE 3.2.1 and my trash folder has suddenly lost the ability to
restore files. The only thing in the context menu on files in trash is
"properties".
I'm finding several bug reports from people who want a restore function for
trashed files, but I'm certain it was there only yesterday... was it or
wasn't it? In any case I want it back!
I've tried making a new user and logging on in a fresh KDE environment, but
there's still no such function.
Can anybody help?
regards,
Niels
...

Strange (to me) behavior in sendmailGreetings! I'm running Fedora 9 at home, with whatever version of
sendmail Fedora supplies. Until recently, I was using it to send weekly
updates on machine status to counter.li.org. Just today, I went there
and noticed that they'd not received an update in over a month.
Concerned, I started looking around and found this in /var/log/maillog:
Oct 27 13:02:18 khorlia sendmail[10628]: m9RK2HDi010628: to=machine-
registration@counter.li.org, ctladdr=joe (500/500), delay=00:00:01,
xdelay=00:00:00, mailer=relay, pri=35695, relay=[127.0.0.1] [127.0.0.1],
dsn=4.0.0, stat=Deferred: Connection refused by [127.0.0.1]
I presume that this means that something's changed, but I don't know
what. Normally, I have my regular email sent through my hosting
company's servers with authentication. Would somebody please post a
pointer to instructions on how I can tell sendmail to do this. (I know
just enough about sendmail to know that you have to be very careful in
changing the config, not enough to know what I'm doing, but just enough
to be aware of my ignorance.)
--
Joe Zeff -- The Guy With The Sideburns:
http://www.zeff.us http://www.lasfs.info
"Ein Volk, Ein Reich, Ein Windows!"
On Mon, 27 Oct 2008 14:42:03 -0700, Knute Johnson wrote:
> One is that I don't have a real domain name for my computer and that
> causes all sorts of problems.
I do have my own domain, zeff.us and my machine's full host name is
khorlia.zeff.us. ...

Strange speedup behaviorI'm a student working on parallel algorithms (using MPI).
I'm seeing this strange speedup behavior. I'm getting speedup greater
then number of processors.
My sequential algorithm is the known graph algorithm and a parallel
algorithm is totally different with same end-results.
(The parallel algorithm is not just the "parallelized" version of the
sequential algorithm.)
In this case is it possible to get speedup greater then the number of
processors?
Thanks,
Ann
[comp.parallel moderator:
The topic term is "superlinear speed up", and it has been a source of
past flame wars in c.p. and in the written litature.
More properly it should be called "superunitary"
[an earlier post of mine cited as a citation in the literature.
But as Jones and others have pointed in from the early 1980s,
when it was first observed, "speed up" is the wrong word;
she suggests "execution time" should it really should be "superunitary
execution time." None of this has stuck.
Regardless of the terms used, it's a great sounding marketing idea,
but it's not something to bank a future one. The behavior will occur
in certain very good conditions in certain classes of algorithms.]
--
Ann wrote:
> I'm a student working on parallel algorithms (using MPI).
>
> I'm seeing this strange speedup behavior. I'm getting speedup greater
> then number of processors.
>
> My sequential algorithm is the kn...

Strange SQL behaviorFolks,
I have a query which selects sales quantities and dollars over a
date range, pretty straightforward.
When I run it to retrieve a small number of results it goes really
quick. Then I retrieve a few more, it's fine. Then I retrieve a
few more, fine, really quick. Once I get over a certain number
of records retrieved, say 270 or so it takes forever.
So, I go from a few seconds to forever, I can't figure it out. What
I'm thinking is possibly the as400 does some weird indexing or
something if it is going to retrieve a lot of rows. Does this
make sense?
Thanks,
Julien
On Nov 30, 1:32=A0pm, Julien Mills <jul...@amorosobaking.com> wrote:
> Folks,
>
> I have a query which selects sales quantities and dollars over a
> date range, pretty straightforward.
>
> When I run it to retrieve a small number of results it goes really
> quick. =A0Then I retrieve a few more, it's fine. =A0Then I retrieve a
> few more, fine, really quick. =A0Once I get over a certain number
> of records retrieved, say 270 or so it takes forever. =A0
>
> So, I go from a few seconds to forever, I can't figure it out. =A0What
> I'm thinking is possibly the as400 does some weird indexing or
> something if it is going to retrieve a lot of rows. =A0Does this
> make sense?
>
> Thanks,
>
> Julien
How big is the file in question?? Are you going after the LF or the
PF.
Use Visual Explain tool, through iSeries Navigat...

Strange undo behavior-----BEGIN PGP SIGNED MESSAGE-----
Hash: SHA1
Oracle 9.2.0.5
Solaris 8
An undo tablespace on one of my databases has been acting strange for
the last week. The undo retention period is 2 hours. Occasionally the
space used in the undo tablespace will go from a few megabytes to almost
10g even though a query of v$undostat for the same time period shows
only 38m of undo has been created. Can anyone explain what is going on?
How do you explain the used space in the undo tablespace going from < 10
meg to almost 10 gig in a space of two hours where v$undostat shows that
< 50m of undo blocks have been written?
SELECT SUM (undoblks) * 8192 / 1048576 mb_used
FROM v$undostat
WHERE begin_time >= SYSDATE - 2 / 24
MB_USED
- ----------
38.4296875
1 row selected.
In that same time period, undo usage went from 10m to 9.5g.
-----BEGIN PGP SIGNATURE-----
Version: GnuPG v1.4.5 (MingW32)
iEYEARECAAYFAkU05EkACgkQzIf+rZpn0oRCFgCcCBgUbdyvpf8jPWcWR139zfev
zAkAn0QzLSzlIJrMJXoWFqYXUvCsgZ9g
=UfZF
-----END PGP SIGNATURE-----
On Oct 17, 10:10 am, Chuck <skilover_nos...@bluebottle.com> wrote:
> -----BEGIN PGP SIGNED MESSAGE-----
> Hash: SHA1
>
> Oracle 9.2.0.5
> Solaris 8
>
> An undo tablespace on one of my databases has been acting strange for
> the last week. The undo retention period is 2 hours. Occasionally the
> space used in the undo tablespace will go from a few megabytes to almost
> 10g even though a query of v$undostat for the same tim...

Strange findfirst behaviorI have a combo box that finds a record on the form, and for the most
part it works fine. But, on occasion it brings me to the record just
before the one I am looking for. If I compact and repair the database
it works correctly again. Sometimes I have to compact and repair
twice.
Any help would be appreciated
It sounds as if something is corrupting the index on the field you are doing
the search on. Please see this link for information on avoiding corruption.
http://www.allenbrowne.com/ser-25.html
--
Wayne Morgan
MS Access MVP
"Shyguy" <shyguy@aol.com> wrote in message
news:j88cq1lf21ndsq90b49t5e1oqlll08ovr0@4ax.com...
>I have a combo box that finds a record on the form, and for the most
> part it works fine. But, on occasion it brings me to the record just
> before the one I am looking for. If I compact and repair the database
> it works correctly again. Sometimes I have to compact and repair
> twice.
>
> Any help would be appreciated
>
Thanks for the link. I'll have to go through it later. ;-)
On Mon, 19 Dec 2005 04:45:03 GMT, "Wayne Morgan"
<comprev_gothroughthenewsgroup@hotmail.com> wrote:
>It sounds as if something is corrupting the index on the field you are doing
>the search on. Please see this link for information on avoiding corruption.
>
>http://www.allenbrowne.com/ser-25.html
...

Strange behavior #2Hi folks
I have an C# app. connecting to a MS-ACCESS database with several tables.
In a specific situations I have problems with a DateTime type in a table.
The problem
is when I want to select records from a table in a specific period the day
and month
seems to be swapped in the query, but it only happens when the swapping
gives a
valid date eg.
12/10/2005 (12. Oct. 2005) returns records on 10/12/2005 (10. Dec. 2005)
23/05/2005 (23. May 2005) returns records correctly since 05/23/2005 is not
a valid date with danish regional settings.
The query is:
"SELECT [ID], [Activity], [BeginDate] FROM TimeReg WHERE [BeginDate] >= #" +
_start + "# " AND [BeginDate] <= #" + _end + "#"
_start and _end are of type DateTime
My PC in running with danish regional settings and if I shift to en-US
settings in the control panel, this
fixes the problem, but that is not a solution for me.
Any suggestions to solve this problem
Thanks in advance.
Kim W.
Hey Kim,
First, the access news groups may be of more assistance than here;
JetSQL in Access is different than TransactSQL in SQL Server, and they
may have some more insight into this.
Obviously, you're running into transation issues because of the
formatting of dates; in the US, 23/05/2005 is not a valid date (since
our date standards default to mm/dd/yyyy). That would explain why
#12/10/2005# would return records in December, because that's the US
standard. As to how to fi...

strange behavior with SPHi everyone,
I got this situation, I got a stored procedure that for some reason
after using it for some period of time (maybe a day or two) stops
sending results, but if I change the position of the condition (where)
on the first line then begins to work ok. This solution works a day or
two but the issue arise again and I must change the line to it's
original version, completing this weird cycle. have you ever seen this
kind of behavior before?
The first commented line is what i need to change time to time...
--Where (Cr.ID_Credito = @ID_Credito Or @ID_Credito = 0)
Where (@ID_Credito = 0 Or Cr.ID_Credito = @ID_Credito)
And (Co.Rut_Cliente = @Rut_Cliente Or @Rut_Cliente = '')
And (Cr.Estado_Credito = @Estado_Credito Or @Estado_Credito = '')
And (Cr.Confirmado= @Confirmado or @Confirmado='')
And (Cr.Estado_Credito in
('CP','AN','CE','CA','EO','AC','CO','CR','CD','JU'))
And (Cr.Rut_Empresa = @Rut_Empresa Or @Rut_Empresa = '')
and (Co.Codigo_Local=@Codigo_Local or @Codigo_Local=0)
and (Cr.Automotora=@Rut_Automotora or @Rut_Automotora='')
and (PE.Rut_persona=@Rut_Persona or @Rut_Persona='')
and (Cr.Confirmado = @Confirmado or @Confirmado='')
and (Cr.Garantizado = @Garantizado or @Garantizado='')
Thanks.
Diego.
ASP, Com+
SQL Server 2005 SP3
Wishmaster ("sysadmin.rock[SINESTO]"@gmail.com)...

Strange IE behaviorI've already resolved this for my part, but I think others may need to
know about it, in case something similar happens to them.
As part of a website development, I wrote a PHP file which worked just
fine under Firefox and Opera, but dropped the session under IE. It
took me ages to track this down. Here's what happened. The URL for the
main page was set up so that if it was called without GET parameters,
it would start a new session. In the normal course of operation, the
main page gets called back with a GET parameter of the form '?
mode=something', which was used by the PHP code to determine the
context in which the page should be run. This worked fine under
Firefox etc., but failed miserably and frustratingly under IE. After
months of effort, I discovered the explanation. IE was requesting the
page twice for each call, once with the GET parameter in the URL, and
the second time without any GET parameters. The server handled each of
these requests as you might expect -- it executed the PHP code twice,
the second time without the GET parameters, which caused it to
terminate the current session. There was no evidence of the second
call anywhere on the screen -- it's entirely unclear to me what
purpose the second request might have served. Once I figured this out,
I worked around it.
So be warned. Under at least some circumstances, whenever you (or one
of your users) requests a PHP page, IE will request it twice, which at
the very least will cause a perfo...

Strange asort behaviorIs anyone able to explain me what's going on here? I really can't
understand!
Create a text file containing just two lines:
1000
10D0
Then use the following simple awk program against it:
{
a[++cnt]=$0;
}
END {
b[1]="1000";
b[2]="10D0";
if (a[1]==b[1]) print "They are equal!";
if (a[2]==b[2]) print "They are equal!";
for (i=1;i<=cnt;i++) {
print i,a[i],b[i];
}
asort(a);
asort(b);
print "Sorted!";
for (i=1;i<=2;i++) {
print i,a[i],b[i];
}
}
Now, the output of this program is:
They are equal!
They are equal!
1 1000 1000
2 10D0 10D0
Sorted!
1 10D0 1000
2 1000 10D0
As you can see, the b array seems to be sorted correctly, while the a
array is inverted!
I'm really unable to figure out what's happening here... can you
kindly help me?
Cld.
Cld wrote:
> Now, the output of this program is:
>
> They are equal!
> They are equal!
> 1 1000 1000
> 2 10D0 10D0
> Sorted!
> 1 10D0 1000
> 2 1000 10D0
>
> As you can see, the b array seems to be sorted correctly, while the a
> array is inverted!
>
> I'm really unable to figure out what's happening here... can you
> kindly help me?
>
> Cld.
Works for me with gawk 3.1.8:
They are equal!
They are equal!
1 1000 1000
2 10D0 10D0
Sorted!
1 1000 1000
2 10D0 10D0
On 14 Dic, 12:08, pk <p...@pk.invalid> wrote:
>
> Works for me with gawk 3.1.8:
>
That's really interesti...

Strange browser behavior?Here's something interesting.
I found a web archive on my drive. I double-clicked it and it chose to
launch MIE, no doubt because the file dates back to before I had Safari
on my machine. (Sure enough, it was created 19 September 2004.)
MIE had no trouble going straight to the URL in question,
<http://www.wfsd.net/wfsd/modules.php?name=Sections&op=listarticles&seci
d=14>
Because, these days, i prefer to use only Safari, i thought I would pen
the same URL in Safari then save as a new web archive.
Guess what � Safari could not find that same page on the web.
Exploring further (he he pun) I quite both browsers and relaunched
them. Inderting the URL in the Address field produced no page in both
browsers.
In other words, MIE can find the address if I click the file but it
cannot find the exact same address if I insert the URl into the address
field, copied-and-pasted from the other MIE window.
Strange or what?
In article <280420061121054181%BusyGuy@Work.ru>,
BusyGuy <BusyGuy@Work.ru> wrote:
> In other words, MIE can find the address if I click the file but it
> cannot find the exact same address if I insert the URl into the address
> field, copied-and-pasted from the other MIE window.
You must have the archive stored locally somewhere.
--
W. Oates
Teal'c: He is concealing something.
O'Neil: Like what?
Teal'c: I am unsure, he is concealing it.
In article
<warren.oates-2987FC.07332728042006@nr-tor01.bellnexxia.n...

Autonumber strange behavior?A record of a table with an autonumber field was accidentally deleted. From
the backup table I made a new table with only the deleted record. Then with
an add query I added that record to the original table. After that, when
adding a new record, the autonumber continued with the last ID value (from
the add query) + 1 there by overriding already existing records.
Is this WAD?
What should be best to do in such a situation?
Thanks,
john
This is a known bug in JET.
See:
Fixing AutoNumbers when Access assigns negatives or duplicates
at:
http://allenbrowne.com/ser-40.html
The article describes the causes, and how to reset the Seed of the
AutoNumber.
--
Allen Browne - Microsoft MVP. Perth, Western Australia
Tips for Access users - http://allenbrowne.com/tips.html
Reply to group, rather than allenbrowne at mvps dot org.
"john" <hgf@neckso.com> wrote in message
news:31f4e$47026136$5354c91b$30439@cache110.multikabel.net...
>A record of a table with an autonumber field was accidentally deleted. From
>the backup table I made a new table with only the deleted record. Then with
>an add query I added that record to the original table. After that, when
>adding a new record, the autonumber continued with the last ID value (from
>the add query) + 1 there by overriding already existing records.
>
> Is this WAD?
>
> What should be best to do in such a situation?
>
> Thanks,
> john
"john" <hgf@neckso...

Strange behavior of CDBonjour les gens,
something strange happens here: My current RISC PC delivers the sound of
a music CD by the 3,5 mm port of the CDROM drive. Is it possible to turn
the signal to go out by the 3,5 mm port at the back of the box or by
the speaker like all other sound of the machine?
Many thanks in advantage.
A.
--
Sent from a Kinetic Risc PC, RISC OS 4.02
Venusberg, European Alps (693 m above sea level)
http://home.chiemgau-net.de/ausserstorfer/
On 3 May, Alex' A. Interrants wrote:
> My current RISC PC delivers the sound of a music CD by the 3,5 mm port
> of the CDROM drive. Is it possible to turn the signal to go out by the
> 3,5 mm port at the back of the box or by the speaker like all other
> sound of the machine?
You should have an audio cable from the rear of the CD-ROM drive to an
audio header on the motherboard - as I recall it is on the right hand
side of the motherboard, alongside the power supply (looking from the
front).
If the cable is present, make sure it hasn't been partially
disconnected. If you don't have one, it's a standard part.
--
Brian Howlett - Email to From: address deleted unseen
-----------------------------------------------------
You can't get the wood, you know!
"Alex' A. Interrants" <bavariasound@usenet.cnntp.org> wrote:
> Bonjour les gens,
>
> something strange happens here: My current RISC PC delivers the sound of a
> music CD by the 3,5 mm port of the CDROM drive...

Very strange keyboard behaviorPlease start Visual Basic (Standard EXE) and press F5. You see an
empty form.
1) Press and hold 'CTRL' + 'A' and then press 'F1'. You shouldn't hear
any beep. I think that's normal.
2) Press and hold 'CTRL' + 'X' and then press 'F1'. Do you hear a
beep?
I do and also Form_KeyDown doesn't recognize 'F1'.
Does anyone has any idea why this behavior and how I can get rid of
it?
Stefan
PS: Same problem with 'CTRL' + 'C' and 'F2'.
On 9 Aug, 21:09, Stefan Mueller <seekw...@yahoo.com> wrote:
> Please start Visual Basic (Standard EXE) and
> press F5. You see an empty form.
> 1) Press and hold 'CTRL' + 'A' and then press
> 'F1'. You shouldn't hear any beep. I think
> that's normal. 2) Press and hold 'CTRL' +
> 'X' and then press 'F1'. Do you hear a beep?
> I do and also Form_KeyDown doesn't recognize
> 'F1'. Does anyone has any idea why this
> behavior and how I can get rid of it?
All this is normal behaviour, Stephan. It is the normal behaviour of a
standard keyboard. It has nothing whatsoever to do with Visual Basic.
I'm not sure whether it is totally down to Windows itself either, and
I suspect the behaviour is partly (or even wholly) due to the keyboard
hardware.
It's a very long time since I was involved with hardware, but I
suspect that the key logic actually reads the key...

Strange iPod sync behavioriPod Touch iOS 4
MacPro Lion
I listen to a lot of extended mp3 interviews often running about 65 MB
each. When I sync them to my iPod, they indicate I am moving 95 files
to my iPod when I am only adding one or two. The good news is that the
sync runs through the mystery ones in less than two seconds so it is not
really a problem. Just wondering if anyone knows why this is happening?
...

Very strange file upload behaviorI tried to search for this issue on the group, but don't even know
where to start, so here's my problem.
We have a very simple form which has a file upload box.
Upon submit the file should be uploaded (using the copy function, from
the server's temp directory to our final directory), the database
should be updated, and the user should be notified of success/failure.
In that order. When we test it at the office, and even from a dial-up
at home, everything is fine.
When my client tries to do it from his cable modem connection here is
what happens: He chooses the file on the form, clicks submit and the
page churns away for a long while. Then, it just goes back to the form
page. In the meantime, the file has been moved to the server's temp
directory, but does not get to our final directory. The database gets
updated (which should only happen after the copy function), but no
confirmation message is given.
Here is some truncated code:
function upload_file()
{
global $target_dir,$target_file;
$upload_temp = $_FILES['filename_new']['tmp_name'];
$upload_file = $_FILES['filename_new']['name'];
$target_dir = "../downloads";
$target_file = $target_dir . "/" . $upload_file;
if (!copy($upload_temp, $target_file))
{
echo "<h4>Failed to upload file...<h4><br>\n";
die();
}
else
{
echo "<h4>Uploaded File Successfully...<h4><br>\n";
return...

strange combo box behaviorThis is wierd:
A client of mine has a combo box on a form that has a list of school
names. She has found a wierd error when she tries to search for a
specific school. She is trying to type in "Communal School of Boston"
in the combo box. After she typed "Comm", the contents of the box
showed "Comm. on School Reform", and the cursor was inserted just
before the period, such that if she continued trying to type
"Communal", the entry in the box turned into "Communal. on School
Reform".
I thought there might be some wierd issue Access was having with the
period, so I updated the name of "Comm. on School Reform" to
"Committee on School Reform". Now, when she tries to type "Communal",
the same thing happens as before, except instead of before the period
the cursor is now inserted before the "i" in "Committee". So she will
see something like this in the combo box: "Communalittee on School
Reform".
To complicate things, this seems to only be happening on that record
(as far as we can tell, they have hundreds).
This behavior is not happening on another machine, so maybe it is OS
specific.
Her machine is XP, DB is Access 2000. The other machine I tried it on
is Win2K. But I have XP and it's not happening on my machine.
Any ideas as to what could cause this?
Thanks in advance,
Jon LaRosa
...

strange bright/blink behaviorHi all.
I hope someone can help me with this code:
/***** foo.c *****/
#include <conio.h>
#include <pc.h>
int
main()
{
unsigned char oldScreen;
oldScreen = ScreenAttrib;
ScreenAttrib |= 0x80; /* sets blink bit */
putch('a');
ScreenAttrib = oldScreen;
return 0;
}
/*****************/
I compile with: gcc foo.c -o foo.exe
My DJGPP installation includes gcc 1.3.1 and djdev203 June 2002 refresh.
OS is Windows 98 SE.
When I launch foo.exe, if the DOS prompt is located at the bottom of the
screen, so that executing foo.exe causes the screen to scroll, all new
lines that are printed also look as they had the blink bit set. Typing
'cls' at the
prompt restores the screen. I tried normvideo(), with no results.
I tried both executing foo.exe in plain DOS or in a Windows DOS box and
I saw the same behavior. What may be happening?
Regards, Jo.
Giorgio Medeot <gmedeot@yahoo.it> wrote:
> When I launch foo.exe, if the DOS prompt is located at the bottom of the
> screen, so that executing foo.exe causes the screen to scroll, all new
> lines that are printed also look as they had the blink bit set.
I suspect that's because the effect of updating "ScreenAttrib" only takes
place if you actually output a character.
I think you should rather use one of the other <conio.h> functions
instead of putch(), which take the attribute as one of their
arguments, and leave ScreenAttrib alone. See, e.g., ScreenPutChar().
...